Biology is a wonderful subject that many students enjoy. But as life would have it (no pun intended), this study is not a favorite of the majority of students who pass through the halls of school. Here are a few questions about biology and some answers to them. So why do we study biology? A lot of students trying to get through school stare at the mountain of work this class involves and struggle through. Some rationalize that it’s good to be well rounded in science or just school in general. I think biology is a sector of science that explains certain things in its area. Some may like it for that reason. A minority love this class for a reason which I cannot explain. Vampires. I mean, just imagine that the person sitting next to you is a vampire and all of a sudden, things don’t seem so bad. The whole irony of this situation is that vampires are dead, which brings us to the second FAQ of biology. What is biology? Biology is basically what it says. Bio - Life. -ology - Study of something. It’s the study of all living things. All the organisms that you can or cannot see. Biology is a huge subject. Biology is so huge that it needs a huge classifying system. And although it is so huge, it has no place for vampires. Because they’re dead. Biology is about life. What do we study in biology? First there’s the obvious, we study life. But life is so much more than someone who can walk and talk and eat and grow. Life has to fit all four points in order to be considered a living organism. Number one, to be alive, one has to contain DNA, number two, all life forms must be able to gain energy and use it in one way or another. The third criteria is, all life forms must be able to sense and respond to their surroundings. The fourth and final criteria is, it must be able to reproduce. That will cancel out a lot of things, but it still leaves millions of things that are considered alive. So in biology we study life. We have to have some way to classify all these...

YOU MAY ALSO FIND THESE DOCUMENTS HELPFUL

...Aerobic Respiration
Breaking down glucose to release energy
Products are Carbon dioxide and water
Diffusion is … the movement of molecules from a region of high concentration to a low concentration until the concentration is equal.
Role of a human circulatory system:
Diffuse In – oxygen (O2), dissolved food (glucose) and water (H2O)
Diffuse Out – carbon dioxide (CO2),waste and water(H2O)
Respiration – releasing energy in cells
Breathing – getting air into and out of your body
Exercise
When you exercise your heart rate and breathing rate increases
Heart rate measured – beats per min.
Breathing rate – counting the number of breaths in a min.
Muscle cells respire faster. Meaning- they need more oxygen and glucose and release more carbon dioxide.
A faster breathing rate means that oxygen can be taken into the body at a faster rate and carbon dioxide can be released faster.
Cardiac output = stroke volume x heart rate
Effects of exercise:
Ventilation – breathing
Respire – release of energy from food/chemicals
Anaerobic respiration
… is release of glucose without using oxygen. This produces lactic acid.
glucose = lactic acid + energy
Advantage: useful for muscles because it can release energy to allow muscles to contract when the heart/lungs can't deliver (O2) and glucose fast enough for aerobic respiration.
Disadvantages: Lactic acid is not removed from the body. It builds up in the body and the blood....

... A group working at the University of California, Berkeley has developed “nanothermometers,” little nanoparticles that can be injected into cells to measure the temperature in various places in the cell. So far, they have been used in cells growing in a culture dish. Indicate what you think the group will discover about the temperature in different parts of the cell. Discuss whether you believe it will be the same or different, and explain why
I feel that the idea of placing a thermometer or nanothermomter inside a cell, that is small enough to fit 60,000 on a head of a needle, is unusual! It helps that they used quantum dots of cadmium and selenium that emit different colors or wavelengths of light that correspond to temperature, so they can see the color change with the instruments. According to an article I found online discussing this research, the information given about the temperatures inside cells is necessary, but lacking among the uncountable terabytes of scientific data available today. The inside of a cell is so complicated, and very little is known about it. When dealing with chemistry, temperature is one of the most important physical factors that can change in a chemical reaction. So, knowing more about the chemistry inside a cell, can tell more about how the chemistry of life occurs. Scientists have long suspected that temperatures may vary inside individual cells, because thousands of biochemical reactions at the basis of life are constantly underway...

...﻿
Cell Shape and Diffusion-Practical Report (Re-Written)
23-04-2012
Year 11 IB Biology
Title: Cell Shape and Diffusion
Diffusion is a type of passive transport which allows particles to move from a region of high concentration to a region of low concentration. In a living system, diffusion involves a cell membrane. Cells also need to excrete waste which also occurs at the cell membrane.
Aim: The aim is to use model cells made from agar which contains phenolphthalein and sodium hydroxide (cut in different sizes) to investigate the effect of shape on the time taken for sulfuric acid to diffuse into the centre of the ‘cells’. This will be measured by the time it takes for the agar to become colourless.
Research Question: How will changing the shape or size of the agar prisms affect the time taken for the sulfuric acid to diffuse into the centre?
Hypothesis: If the surface area to volume ratio of the agar prism is large (eg: 1 x 1 cm), then the time taken for the sulfuric acid to diffuse it will be shorter. The smaller the size of the agar block, less time will be needed to diffuse the agar block compared to a larger agar block with a lower SA: V ratio.
Variables: The independent variable was the shapes of the agar prisms and its sizes. The surface area to volume ratio (cm 2 : cm 3 ). The sizes and shapes used were:
Dimensions of each agar block: Table 1
Shape
Dimensions (cm)
Cube 1
1 x 1 x 1cm
Cube 2
1.5 x 1.5 x 1.5cm
Cube 3
2...

...
Male System
The structure and function of the human male reproductive system, is very similar to that of many other mammals. The male system is designed to make sperm or male gametes and is adapted to provide for the delivery of these gametes to the female to allow for fertilization.
Male Reproductive System
Male Reproductive System Structures
1. testes -- produces sperm and the hormone testosterone
2. scrotum -- pouch enclosing the testes keeping the sperm at an optimum temperature for development
3. vas deferens -- tube carrying sperm away from the testes
4. prostate gland -- the largest of several glands which add lubricating and other fluids to the sperm
-- this combination of sperm and fluids is called semen
5. urethra -- tube through the penis carrying sperm to the outside of the body
6. penis -- adaptation for internal fertilization of the female
Female System
The structure and function of the human female reproductive system, is very similar to that of many other mammals. It is designed to produce female gametes or eggs, allow for internal fertilization, support the internal development of the embryo and fetus, and provide nutrition through milk for the newborn.
Female Reproductive System
Female Reproductive System Structures
1. ovary -- (females have two of these) -- produce female gametes or eggs and the hormone estrogen
2. oviduct (fallopian tube) -- carries the egg away from the uterus
--...

...
Name________________ Block 4 ______
Pushing the Limits – Strength!
For each section: List ONE question that could be answered by the film about each of the different sections and state the answer.
Bones
Q - How Many bones is your skeleton made up of ? _______________________________________________________________________
A - The Skeleton is made up of 206 bones _______________________________________________________________________
Muscles – Superhuman strength
Q- How does muscle tissue work?
_______________________________________________________________________
A- muscle tissue works by pulling and contracting, acting like a lever. _______________________________________________________________________
Skeleton and Cartilage – Shock Absorption
Q - How much weight can knee cartilage handle before breaking
_______________________________________________________________________
A- 7 tons _______________________________________________________________________
Pain Tolerance
Q- can you train to have a high pain tolerance? _______________________________________________________________________
A- Yes _______________________________________________________________________
Adrenaline - Fight or Flight
Q-what does adrenaline do?
_______________________________________________________________________
A- It heightens speed and reaction time and gives strength that you didn't know you had....

...1. If an endangered species such as the Santa River Woolly Star were to become extinct, what effects might this have on other species?
The community of organisms will be greatly affected if the Santa River Woolly Star were to become extinct. The Woolly Star is an interwoven strand in a crossing of organisms that are all dependent upon one another for survival. The Woolly Star also stabilizes the sand after flooding which has a [positive effect on other organisms.
2. What do the J- and S- shaped population curves indicate about the life span of an organism?
Organisms that live in a temporary habitat are examples of J shape growth curve. J shape growth curve indicates that the organisms outgrow the amount of resources available and death rates increase. S shaped growth curve organisms are affected by the more organisms in the population the more limiting the environment is to population growth. Population size in S shape double as it does in J shape however as more organisms appear they compete for limited resources in time the population stabilizes at a rate the environment can sustain.
3. Does competitive exclusion limit the diversity within a given community?
Competitive exclusion will eventually limit diversity. As both species compete for a food surface one will typically dominate and the other would become extinct and therefore there would be limited diversity.
4. Why are field studies, such as the monitoring of owls, important in the study of ecology?
The...

...
Introduction to Biology, Lesson 3 Essay Questions:
Compare and contrast directional selection and disruptive selection, and provide an example of each.
Both of these show the distribution of phenotypes. In directional selection, the distribution of phenotypes forms a "bell curve." Selection against one of the extreme phenotypes causes the distribution to move in one direction or the other. An example might be plants whose flower color is determined by incomplete dominance: white, pink, or red. Pink flowers may be the average phenotype, but if we start to remove red flowers from the population, the "mean" phenotype will be shifted toward white flowers.
In disruptive selection, the average phenotype is selected against. This produces a "two-humped" bell-type curve, and the greater distribution is split between the two phenotype extremes. If we have the same type of incomplete dominance as mentioned in the previous paragraph, assume that the pink flowers are selected against. This means that the two humps shown in the distribution will be centered on the red and white phenotypes.
Many pathogenic bacteria species are becoming resistant to antibiotics. Explain how such adaptations can develop through the process of natural selection. (Hint: Relate this example to the conditions that are necessary for natural selection to occur.)
Antibiotic resistance is the ability of a microorganism to withstand the effects of an antibiotic. It is a specific type of drug...